As is known, chemical and biological assays are typically performed in a plurality of multi-well plates. These multi-well plates include a large number of wells that are filled with user desired reagents. The current industry standard requires each multi-well plate to have 96 or 384 wells therein. While each of the wells of the multi-well plates only holds a few microliters, the cumulative volume of reagents required to fill all of the wells can be significant. Since the production of sufficient volumes of the reagents is often time consuming, as well as, expensive, it is highly desirable to provide a method of performing chemical and biological assays utilizing smaller volumes of reagents than prior methods.
Given the large number of wells in the multi-well plates, specialized equipment has been developed in order to quickly and efficiently conduct the chemical and biological assays. For example, specialized equipment is needed to generate the various concentrations of reagents required and to fill each well of the multi-well plate therewith. Further, additional equipment is often necessary to transport the multi-well plates to a user desired location for observation. As such, it is highly desirable to provide a method of performing chemical and biological assays which may be performed more quickly and more simply than prior methods.
Therefore, it is a primary object and feature of the present invention to provide a method of performing chemical and biological assays using smaller volumes of reagent than prior methods.
It is a further object and feature of the present invention to provide a method of performing chemical and biological assays that requires the use of less specialized equipment than prior methods.
It is a still further object and feature of the present invention to provide a method of performing chemical and biological assays that is simpler and less expensive than prior methods.
It is a still further object and feature of the present invention to provide a method of performing chemical and biological assays that is more efficient than prior methods.
In accordance with the present invention, a method of performing a gradient-based assay in a microfluidic device is provided. The method includes the step of providing a microfluidic device having a channel therethrough. The channel is partially defined by a channel while extending along an axis. A plurality of targets are axially spaced along the channel wall. A stream of first fluid is introduced into the channel so as to flow therethrough. The first fluid stream has a predetermined concentration of particles therein. A stream of second fluid is introduced into the channel so as to flow therethrough. The particles in the first fluid stream diffuse into the second fluid stream so as to cause a gradient of concentration of particles in the second fluid stream. The predetermined concentration of particles in the second fluid stream intersect corresponding targets as a second fluid stream flows therepast.
The channel has first and second sides and first and second ends. The channel wall extends along the second side of the channel. The first fluid stream is introduced in the first side of the channel adjacent the first end thereof and the second fluid stream is introduced in the second side of the channel adjacent the first end thereof. The targets are bound to the channel wall or may include a plurality of wells spaced along the channel wall. Further, the targets may include a plurality of sample channels extending from the channel. As such, it is anticipated that portions of the second fluid stream flow into corresponding sample channels. A visual display may be generated in response to the intersection of the second fluid stream and the targets.
In accordance with a further aspect of the present invention, a method of performing a gradient-based assay in a microfluidic device is provided. The microfluidic device has a channel therethrough. The channel is partially defined by a channel wall extending along an axis. The method includes the steps of providing a plurality of targets axially spaced along the channel wall and providing first and second fluids. The first fluid has a predetermined concentration of particles therein. The first and second fluids are passed through the channel such that the particles in the first fluid diffuse into the second fluid so as to cause a gradient of concentration of particles in the second fluid as the second fluid flows through the channel. The predetermined concentration of particles in the second fluid intersect corresponding targets as the second fluid flows therepast.
The channel has first and second sides and first and second ends. The channel wall extends along the second side of the channel. The first fluid is introduced in the first side of the channel adjacent the first end thereof and the second fluid is introduced in the second side of the channel adjacent the second thereof. The targets may be bound to the channel wall; include a plurality of wells spaced along the channel; or include a plurality of sample channels extending from the channel wall wherein portions of the second fluid flow into corresponding sample channels. A visual display is generated in response to the intersection of the second fluid and the targets.
In accordance with a further aspect of the present invention, a method is provided for performing a gradient-based assay in a microfluidic device having a channel therethrough. The channel is partially defined by a channel wall extending along an axis. The method includes the steps of passing a first fluid through the channel and passing a second fluid through a channel. The first fluid has a predetermined concentration of particles therein such that particles in the first fluid diffuse into the second fluid so as to cause a gradient of particles in the second fluid as the second fluid flows through the channel. The second fluid sequentially intersects a series of targets along the channel wall as the second fluid flows through the channel.
The channel has first and second sides and first and second ends and the channel wall extends along the first side of the channel. The method of the present invention may include the additional steps of introducing the first fluid in the first side of the channel adjacent the first end thereof and introducing the second fluid in the second side of the channel adjacent the first end thereof. The targets may be bound to the channel wall; include a plurality of wells spaced along the channel wall; or include a plurality of sample channels extending from the channel. If the targets include a plurality of sample channels, the method includes the additional step of drawing portions of the second fluid into corresponding sample channels as the second fluid passes therepast. A visual display may be generated in response to the intersection of the second fluid and the targets.